Sharp flame burner



H. w. NIEMAN 3,038,529

SHARP FLAME BURNER Filed Feb. 2, 1960 IN VE NTOR Henry l/ A//kffman ATTORNEY United States arent @hace 3,038,529 Patented June 12, 1962 3,038,529 SHARP FLAME BURNER Henry W. Nieman, Bethlehem, Pa., assigner to Bethlehem Apparatus Company, Inc., Hellertown, Pa., a corporation of Pennsylvania Filed Feb. 2, 1960, Ser. No. 6,231 1 Claim. (Cl. 15S-27.4)

This invention relates in general to gaseous fuel burners, and more particularly to gas-oxygen burners for high temperature work.

With such burners, which have special utility for glassworking and the like, the gas must be very rapidly and intimately mixed with the oxygen for complete combustion and highest temperatures, and also to obtain a uniform flame of pointed slender shape which can be precisely directed and controlled.

It is an object `of this invention to provide a burner having a novel arrangement of tubes and passages which will always maintain an extremely hot sharp llame through a wide range of adjustments of the usual valves controlling the flow of gas andl oxygen thereto.

Another object is to provide a burner having such an arrangement which includes a central tube and a series of planetary tubes, with each of the latter tubes being in spaced relation to the adjacent tube and in heat conductive contact `to the central tube, and securely locked in that position by two points on opposite sides of a median line.

A further advantage of this burner is that its llame cannot ash back and is almost impossible to be blown out accidentally.

Other objects, advantages and purposes of the invention will appear hereinafter in the specication and claim, and in the appended sheet of drawings.

In the drawings:

FIGURE l is a front view of the face of a preferred form of the burner;

FIG. 2 is a cross-sectional View of the tip of the burner, taken on the line 2-2 of FIG. l;

FIG. 3 is :a cross-section of said burner on the line 3-3 of FIG. 2; and

FIGS. 4, 5 and 6 are front views of the faces of alternative forms of burners constructed in accordance with this invention, With corresponding parts being indicated by the reference numerals which are followed by letters.

Referring to FIGS. l-3, the reference numeral 11 designates a circular tubular outer casing of small diameter coaxially enclosing an inner tube 12 of suiiiciently smaller outside diameter than the bore of said casing to provide an annular space 13 for oxygen flow around the tube 12. The rear ends of one small central tube 14 and live evenly spaced planetary small tubes 15 are brazed together on their outer surfaces as a bundle and into the forward end of the tube 12, being held therein by a gastight deposit of brazing metal 16. The front ends of the five small tubes 15 are held tightly around the central tube 14 in an exact conguration in the live evenly spaced grooves or flutes 17 in the substantially circular opening 18 in the end bushing 19, which latter bushing may be made integral with the casing 11, or brazed therein as here shown, at the forward end of the burner. Each of said flutes 17 has straight converging sides Ztl which tangentially engage each of the planetary tubes 15 on two sides and have sufficient depth at their pointed ends 21 to provide a space 22 for the passage of oxygen on the outer side of each of the tubes 15. More than live planetary tubes 15, however, tend to interfere unduly with the oxygen supply needed for combustion.

Fuel gas such as hydrogen is admitted through the tube 12, passes through the small tubes 14 and 15, and discharges at the front face of the burner. Oxygen ad- 2 mitted through the annular space 13 is discharged through the spaces 23 between the small tubes 14 and 15, and also through the spaces 22 at lthe ends of the flutes 17. Each jet of gas is therefore virtually surrounded by jets of `oxygen so that an intimate mix-ture forms at the open front face of the burner 'and burns with intense heat. All the tightly packed tubes 14 and 15 are cooled very effectively by their conduction of heat from the central tube 14 to the bushing 19 and thence to the casing 11, this being particularly necessary to prevent excessive overheating and consequent deterioration of said central tube.

In each of the alternative types shown in lFIGS. 4, 5 and 6, all the small tubes are likewise tightly packed in arrangements which permit free access of oxygen to the spaces between the tubes, and are also rmly positioned by the interior flutes of the encircling bushing. In FIG. 4, the four flutes 17a position a central tube 14a and four planetary `tubes 15a which are all of equal size and provide large oxygen outlets. The central tubes 14h and 14C of FIGS. 5 and 6 have decreasingly smaller relative sizes, with their utes 17b and 17C being respectively four and three in numbers corresponding to the planetary, tubes 15b and 15e, and are still very lirmly held together. With three planetary tubes 15C as in FIG. 6, it will be noted that the central hole 18o in the bushing 19e may be substantially triangular, with the three long sides 24 forming utes 17C ending in blunt ends 21e.

It is important for several factors to be kept particularly in mind with regard to the present invention: tirst, in order to obtain smooth laminar gas flow, all the small tubes must be extremely small, of the type used in hypodermic needles, and are therefore quite weak and easily bent; second, there must be considerable longitudinal space between the tube 12 and the bushing 19 so that the oxygen can assume a straight line flow between the tubesy before it reaches the burner face; and lastly, almost perfect symmetry of flame is demanded by those who use the burner.

The geometrical arrangement which insures the locking of the planetary tubes in fixed contact with the central tube and in fixed spaced relationship to each of its adjacent planetary tubes is essentially the same in all of the burners shown. With particular reference to FIG. 4, a typical median line OA may be taken radially from the center O of the central tube 14a through the center of any one of the planetary tubes 15a to a point A. Firm contact of said planetary tube with the central tube 14a and a rigidly fixed spaced relationship with respect to the two adjacent planetary tubes 15a are effected by providing for two points of contact between each planetary tube and its flute 17a in the surrounding bushing 19a, each of the two points of contact between said planetary tube and the bushing being on opposite sides of the line OA.

With this burner, ashback is impossibl-e, because the mixing of the oxygen and gas takes place only after they have left the burner separately, and yet complete combustion occurs within a very short distance from the front of the burner.

By the advantageous utilization of closely packed and rmly positioned gas tubes with ample oxygen supply around them, there is produced a slender, sharply pointed and symmetrical flame of high intensity and having many industrial and laboratory uses.

Although the invention has been described herein- -above in considerable detail, it is not desired to limit the invention narrowly to the exact and specic details described, but there may also be used such substitutions, modications or equivalents thereof as are included within the scope and spirit of the invention or pointed out in the appended claims.

I claim:

In a burner:

(a) a central tube;

(b) a plurality of not less than three nor more than ve parallel planetary tubes surrounding said central tube;

(c) a bushing surrounding said planetary tubes;

(d) yan outer casing surrounding said bushings;

(e) the aforesaid bushing having evenly spaced angular flutes;

(f) each flute engaging a planetary tube at at least two points;

(g) each planetary tube being in fixed heat-conductive contact with the central tube and a flute, and also being in xed spaced relationship to the two adjacent planetary tubes;

(h) said fixed spaced relationship being effected by one of the aforesaid points being on one side of a line from the center of the central tube through the center of said planetary tube and the other of said points being on the opposite side of said line;

(i) each ute providing substantial unobstructed space between the inner face of said bushing and the outer face of its planetary tube between the two said points;

(j) means for supplying fuel gas `to said central tube and to each of the planetary tubes;

(k) and means for supplying `oxygen to each space between the tubes and to each of the aforesaid unobstructed spaces.

References Cited in the le of this patent UNITED STATES PATENTS 352,771 Moorehouse Nov. 16, 1886 1,721,381 Ellis July 16, 1929 2,015,931r Hepburn Oct. 1, 1935 2,143,841 Byrne Jan. 17, 1939 2,911,035 Nieman etal Nov. 3, 1959 

